We are honored today to have a group of engineers, heroes, i tried to get her to follow in your footsteps as quickly as i could since 1959. We will have a panel talking about lunar module lending operations today and if you want to know what that is they will tell you about it. As we go around we have the panel here jack knight to the immediate left, bob nance, bill reeves and hal loden, i will have them identify themselves briefly and say a little about what they did and then open it a little for questions and since i didnt introduce myself, my name is john charles and im a scientist here is the center, houston. I would like to turn the microphone over to mr. Knight to talk about what you did to apollo 11 and what brought you here in the first place in your recognition of that important day. Okay. I was the son of an air force family and we were in various places around the world and i went to Georgia Institute of technology and came directly here to the Space Flight Center and was hired by the Operations Area and in particular the apollo systems group. At the time that i arrived, apollo had been is a programming work but we were flying the gemini and the gina vehicles. I was in the Environmental Control and electrical power area and i participated in every lunar module flight, including the first unmanned one and, i was in the ss our Staff Support room for that in a all subsequent flights i was in the Mission Operation control room in a position we call telecom depending on the flight you are talking about. That was apollo 9 to apollo 11 and everything that had a lunar module on it. I will pass it on to bob. [ applause ] good morning this is a big day. I started this morning with a prayer just like 50 years ago the lord please help me not to screw up today. [ laughter ] my name is bob and in 1962 i heard president john kennedy tell the world that we were going to go to the moon by the end of the decade and i wanted to be a part of that and everything from then on went on and i went to georgia tech and the astronaut john young was there and through him and it appear from georgia tech to man the spacecraft sooner in lunar module potion propulsion. I was so blessed to live my dream of eating on the consul of the lunar module when we landed on the moon i think we will talk a lot about that later. [ applause ] good morning. My name is hal loden, i grew up in texas and my dad was a methodist preacher and we worked around a lot. I was in florida working on a Space Program in 1963 through 1964 which was a langley project and he said, why dont you go to houston and man the spacecraft center. Im from houston and my wife is from houston and said that would be great see i got a job here. I went in to the Operations Directorate and i was with the gemini and gina systems. To back up just a second i have a nearby education from texas a m. Woop [ laughter ] during apollo 11 i was a flight controller during the lunar module gmc systems area but they had a few control systems and the hardware for the primary and backup Computer Systems but there was a remote site in australia for that and apollo 9, 10, 11, 12 through 17 relied on the flight from michigan troll for the lunar module. Specifically on apollo 11 i was the control guy on console from the ascent from the moon. The descent was exciting, i was there sitting behind our good friend bob carlton who did the descent, hes no longer with us, he passed away a few months ago. But, i was a little hesitant, whether we would make it because we didnt have a lot left, did we crack but, you know, when i got to the ascent we had problems also. I heard people say the ascent was riskier than the descent and i find it harder to believe but anyway, thats my story and i will pass this over to bill reeves. [ applause ] good morning. My name is bill reeves and i grew up in arkansas and went to oklahoma, ou to get an Electrical Engineering degree and want appear in texas as fast as i could. So, when it came to football season i didnt have a chance growing up in arkansas, ou and texas. But, anyway, when i hired on in 1967 i hired on into Flight Operations director and the Flight Division and is a flight controller on the lunar module in the electrical power system group, we were in charge of all of the Power Systems and Power Distribution systems of lunar module and, we were also in charge of the pyrotechnic system which were the explosive devices that step rate the stages and open valves and do that kind of thing into play landing gear. Then, so, i had gotten here right after the apollo 1 fire that happened in january, so, the program was in a delay while they figured out what happened and got back flying again which turned out to give me the time i needed to get on board and was lucky enough to be in position we started applying the lunar module. I was in the staffs of which, the support rooms are the rooms that support control room and, we are the people that made the people in the main room look good. So, when you see the control center, when you go over to see the control center and when you see it on the movies and everything thats the tip of an extremely large iceberg. Theres a lot of people supporting that and then i controlled part of the lunar module through all the flights and through the program and then after apollo was over, i flew back to do airplanes for a few years and then came back to operations for shuttle and was a flight controller on the shuttle and then later selected as a light direct for 22 shuttle flights. And thats it. [ applause ] this is excellent, this is a good thumbnail sketch of lunar module at for apollo. I started my duties and when we first came in we are finished here please move quick read to the exits there are 200 more people outside waiting for the next presentation. I would like to ask a question and then we opened up for q a and we will talk about the two lunar module propulsion activity modules, one is the power descent and one is the powera sent and i will talk with mr. Nance about your recollections and any cosmos you had about the Lunar Landing and the propulsion down from lunar orbit and your recollections and thoughts about the probability of success, the inevitability of six or any sweaty palms you might have had. Yes, there were a lot of sweaty palms. That is a broad area, but let me try to give an overview. First of all, the lunar module descent starts shortly after the lunar module comes back around from the backside of the moon. The big surprise we had and i think jack mentioned it in the previous session was that the data was so difficult that we were having trouble getting voice and data and high gain data and, as we started the dissent of the engine fired in the first thing that happened was the data dropped out so we are getting go no goes without data and a lot of time you hear the landing and it sounds like everything went really smooth, but, it was difficult at the the beginning. The data would drop out and we would get a little bit of data and hope everything is working good and then we got our data back and then we came to the part where the crew starts off with their headdown so they can see the lunar surface, they lean over and rotate, 1800 and when that happened we lost data again. So it first it seemed are we really going to be able to land, but the great news is we started getting good data, everything was looking good, we did hear that we were going to be long and we knew that from the very beginning. We had a slight timing error when the burn started, but everything was going very smooth. One of my jobs and, i shouldve mentioned before, i was in charge of the ascent, descent and reaction control, the thrusters that you see out on the lunar module. A lot of people think, wow, you just concentrated on the descent engine but we actually had to have a visual pattern where you would look at the ascent and the rcs because you are burning in engine, the vehicle is shaking, you wanted to make sure if the descent engine was working good, maybe the ascent was bringing a leak or something bad was happening there. So even though you were concentrating on the descent you constantly had to look at other systems in the various propulsion systems. We start off burning at about 98 thrust and then it drops, it dropped in six minutes and 25 seconds and by then we had data, everything was looking pretty good. Everything was just tracking, we had a few computer problems that you heard about, and overload on the computer, the 1202 and later at 1201. And everything seemed to settle down and every thing was going good. One of the things that we were always a little worried, was a fuel margin on the first mission. It was running about 4 1 2 . Propellant remaining. It was looking pretty good. Then we heard attitude hold. Attitude hold is when the crew decides to take over themselves. Normally if they did nothing the limb what actually come all the way down. Right to the moment just before landing. We already knew from simulations that we did with neil that he liked to take over early but this is way earlier than we normally had seen. So we knew that something was going on. One of my jobs was of course propellant monitoring, are we going to run out of fuel. So we had sat in a meeting with neil and buzz and worked out what we were going to do. We first had an indication of low level, that is 5. 6 propellant remaining. We knew that, the goal was at that time you knew approximately how much time you had to have her. To be honest with you we got to 5. 6 and they werent anywhere close to hovering. Because neil had realized he had to go down over the top of the crater and hit away from a Boulder Field and try to find smooth ground to land. We could see this happening because the rcs, those little jets, normally descent engine has a bell and it moves to control the small motions that are made with it. And you see the rcs that means hes overwriting it, hes putting in a command that is greater than the descent engine can move that fast. So he had moved over to speed up. He stopped descending, actually he went up a little bit and im sure that was to see where he could find a clear spot to land. Then the next call was 60 seconds, thats 60 seconds until you run out. Thats not 60 seconds until you have to make up your mind. The calls were 60, 30, and bingo. 60 seconds, 30 seconds and bingo. And as i mentioned in the meeting, we sat there in, and my original idea was 60, 30 and 15. And buzz kind of talked a lot and was pretty active and neil was always very quiet. After quite a while of talking about this, all of a sudden neil says, i dont like abort. Because im a pilot. And i will make that decision. And i said we know that you will. Mr. Armstrong. [ laughter ] so he turned around and said can yall give that another name please . And i believe buzz was a navy pilot and he says well in an Aircraft Carrier when you are committed to land and you have demand, you have to land no matter what you say bingo. And neil said bingo works. So it was 6030 bingo. The problem with that was i never expected to call 30, in simulations we normally landed shortly after 60 seconds. Actually i have a website called robert nance apollo 11. Com and i have all of those tapes and you can actually here, you can hear the ss are talking to control, and when i made the 62nd call that was passed on, it was 60 seconds. When i made the 32nd callout it was more like 30 seconds like i didnt believe him a i couldnt believe it went here. The final number after a lot of analyzation was we landed with 22 seconds of fuel remaining. In addition to all of that we had a problem of slosh but thats another story for another day. But the interesting thing about this is, i think its really important that the public understand just how brave neil and buzz were. I mean there were so many things, people dont realize, they think well we said other missions there, this was the very first time we had ever landed any spacecraft like this. All the other missions, as you heard about, ranger and surveyor, landed directly. You couldnt do that with men on board, if anything happened you had no way to stop it and start back up, the absent would not have enough propellant. So we landed a little different by starting a little different and going down slowly. This was the first time that these computers which had very little memory, this was the very first time that was ever done. And if you want to applaud somebody you applied neil and buzz. [ applause ] thank you. And skipping over an awful lot of interesting stuff, i would like to ask mr. Lowden about the asset, about the power to set powered asset and if you could say a few words about the unique ascent propulsion system. Okay, lets see what i can come up with here. 50 years is a long time ago. To remember all the details. As you remember during descent we had those 1202, 1201 alarms and it gave everybody a lot of concern. That was because the onboard computer was being overloaded doing tasks that it didnt really need to be doing. It had to do with rendezvous of radar and trying to keep track of where the csm was in that kind of thing. So when it came to ascent, there was quite a few precheck list changes that had to be made to take into account that potential problem again showing up possibly on ascent, we did not want that to happen. We wanted to keep those alarms from happening. So one of the changes that was made, we came up with a procedure to stow the rendezvous radar antenna and to power off the rendezvous radar during ascent. There was another issue that i remember working, when they came back in from their eva, buzz noted the Circuit Breaker panels on both sides of the lunar module, on the inside, the Circuit Breakers are not like the Circuit Breaker panels were used where you flick it like a light switch, these are ones that you push in and pull out. The Circuit Breakers for all of these, most of these were already out which is the off position. And he noticed once he got back in the lunar model the Circuit Breaker was broken off. It happened to be the ascent engine arm Circuit Breaker. That doesnt mean were not going to be able to light the ascent engine, we have two ways of doing it and that one allowed the computer to automatically light it. We have a manual work around with another pushbutton. So trying to figure out what to do, as i understand it he took out his trusty government issue black ballpoint pen, pushed it in. During the countdown at the right time for ascent. The other thing that occurred leading up to ascent on the ascent propulsion system, the fuel tanks, we had two pressurization bottles for redundancy to pressurize the fuel tanks. To get the fuel at the right pressure and everything before it goes into the stress chamber of the ascent engine. And during simulations, these were pyrotechnic we operated valves to open up the tanks to pressurize the fuel tanks, normally during simulation we would always see both of those tanks drop a couple of psi or pcm counts is what we call them. That would confirm that both valves had opened. When it came time to do it on the lunar surface and they fired the valves to pressurize the ascent engine so they could lift off, i only saw one ball drop, i didnt see the other bottle drop, which gave us the possibility we only had one bottle of pressurization on the fuel tanks. Part of the normal procedure for absent ascent, we had a system interconnect between the ascent engine and the reaction control system, the thrusters that bob was talking about. We had to, they had to both use the same propellant and we could use the ascent engine propellant out of its tanks to also fire the attitude control system. On the way up. But if we only had one bottle of pressurization we had to terminate that interconnect, it is called ascent feed. So we had to alert the crew that that was a possibility, that really and truly we only had one bottle pressurized, and we would have to terminate ascent feed on the way up. So the countdown to t0 was done by the computer. The procedure also called for charlie after takeoff, they already hit this engine fire override button which circumvented the command coming out of the computer just in case the computer on command went away for some reason and the engine would still stay on. So at lift off, a few seconds after liftoff we had both bottles, so i was very relieved about that. And to tell them continue on with ascent feed. From then on, i noticed that they had not hit the engine fire override either, the second way of keeping the engine on. So finally about halfway up they finally enter energized the route for keeping the engine on. So those are the things that occurred for me during ascent and as far as the ascent engine, it was about 3500 pound thrust engine, it wasnt very big, about 4 feet tall and 3 foot in diameter, no big deal. At the ascent stage it weighed 10 or 11,000 pounds. So it did its job very well. If you notice on the films, of ascent, when they are looking out the window you can see it kind of rocking back and forth, and that of the attitude control system and that is what the attitude control thrusters are keeping it within that , the ascent engine was not forgivable like the descent engine was. Once we got back in orbit, they talked with Amanda Service module, got back into command Service Module and discarded our eagle which impacted on the moon after they left the moon. So it was a very good engine, a very reliable engine, and i was very grateful to be a part of such a great event. Thank you. [ applause ] before we leave that topic i do want to drill down on one point and that is how many test firings did the ascent engine have before the flight . That is a question i do not knew the answer to. I would assume it had gone through a lot of tests firings as well as probably some in vacuum chambers as well, but both the descent and the ascent engines were thoroughly checked out before the descent had a capability that we had never had before on a spacecraft. The people that put these machines together were very dedicated. That is the part of the iceberg bill was talking about a while ago. Those people that built the spacecrafts and the components that went into the spacecraft are the ones who made it happen. That wasnt a gotcha question, there is a very particular aspect of this that i would like to let you know about. Its not my area that i have read quite a bit of things over the years. It is part of nasas Development Process when they felt there was an area that was highly risky, they would higher two contractors to work on it in parallel. So there were two different contractors who worked on the ascent engine and they finally got to the point where one of them was more successful, or successful enough and so nasa said okay you are it. You can go build ascent engines. One of the thing about the ascent engine was, its injector was such that erosion during firing wasnt so bad they could only fire at once. So they did a lot of testing until you certified that but after that, no ascent engine was ever testfired before it was used for actual launch. Descent engine was probably different but thats an interesting story on the ascent engine but as you said its a simple engine, a hyperbolic fuel, all you had to do was get it to mix and it would work. And we knew from testing that it would work at least once. [ laughter ] and thats all it had to work. And thats a good point jack, that i had not remembered. The first time we let that sucker was on the lunar surface. [ laughter ] that is pretty risky when you think about it. [ laughter ] you know i was in a meeting with, i think it was actually a debriefing from one of our simulations so we really did love those, they were sometimes difficult where we missed a problem or something, but i remember neil saying why in the world didnt we just put a big lever on the side because the actual top of the engine looks like a seat sitting in the middle of the lunar module, he said why in the world didnt we just put a big handle on it where you just turned it and it starts. [ laughter ] that would not necessarily have worked during an abort stage during the power descent. [ laughter ] let me add another thing. Bob mentioned the loss of calm. When it came around the moon for power descent the engine was essentially pointing toward the earth. So the high gain antenna had to point through the landing gear and whatnot to get to the earths antennas. One of the things that was added late in the game, was the deflectors on the descent stage that were right underneath the down firing thrusters, they were added late in the game because the thermal analysis said there might be enough erosion caused by those thrusters that it would damage the thermal protection on the descent stage so they put those little deflectors. Because it was very late in the game, those deflectors were never included in the modeling of antenna pointing, and getting good communications. So the calm guys, im pretty sure thats what happened, we started the descent engines and as you are coming around the antenna was basically trying to point through one or more of those deflectors. So we had ratty communications until we moved a bit and reoriented the antenna. And because neil wanted to be looking down at the moon you had this other maneuver, the 1800 turn he was talking about after you started the descent engine, it ran a little while then you had to roll it over. So that when it pitched forward, armstrong and buzz would be able to see where they were going. All subsequent flights the crew decided they didnt need to be looking down, they could just get in their anticipated position and then all they would have to do was pitch forward. You would not have to have that maneuver. That is probably why we ended up with communication problems, until they had pitched forward enough and moved enough across the surface, the steerable antenna got good enough direct munication with the ground. Im glad you mentioned those rcs thrust, in fact one interesting thing about that like you said, this was the first lunar module that had them installed. The reason they were installed is like you said, with that downward faster, thruster, it would impede and potentially cause damage. And as i recall there was a limit placed on impingement of a maximum of 15 seconds on the descent stage or they would have to terminate, so these thrust effectors eliminated that problem because on apollo 11 it would have exceeded that limit according to Data Analysis afterwards. So they wouldve probably aborted if we had not have those thruster deflectors on there. I was going to say, there were a lot of great Neil Armstrong sayings getting ready for this thing, and one of my favorite stories, and all of us old people remember things differently but this is the way i remember it. Late in the game, with the landing radar that was on the lunar module, to tell you how high you are, there had been some problems in testing with the landing radar locking on at the distance it was designed to lock on and so there was a lot of concern about whether it was going to be giving the data they needed. So they had done a lot of testing on it and we were in a flight rule meeting, i remember it like it was yesterday. It was a very large room with a lot of people in it and there was a big long white table with jean krantz who was chairing the meeting and neil was sitting at the end of the table and it was a discussion about developing a flight rule that said if the computer was not accepting landing radar data by x altitude it would be an abort and the altitude would be calculated. So they argued it for like two or three hours and finally jean says okay guys, thats it weve talked about this long enough, thats the rule. If the computer is not accepting radar data by x altitude calculate it out and its an abort. Everyone is nodding their heads and neil was sitting at the end of the table with his had in his hand and just shaking his had and all of a sudden krantz saw him and said whats the matter neil . You dont agree with this . And he said you must think im going to land with the window shades down. [ laughter ] i think that is the only mission rule meeting i remember. I dont like to remember them because the room was full of nothing but smoke. It was a different time then. We have times they shall have time for a few questions from the audience, does anyone have questions . Please shouted out and i will repeat it for the cspan audience. How far down range did they land from the target site . It was about 3. 7 miles but it was well within the ellipse. They were down range and slightly to the left. And i did mention before i actually was looking all of this up in case you asked that question, i didnt know it a week ago and i did put it on the website. It is robert nance apollo 11. Com if you want to look up that kind of stuff. The question is compared to the smart phone how much Computing Power did we have back then. One picture on your cell phone has more bits in it than that computer on the lunar module. Why did the lunar module carry jumper cables . Did you know we carry jumper cables . We didnt have to carry jumper cables, i guess we had diehard batteries on board because we didnt need them. If our batteries didnt work none of their stuff would work. There werent any jumper cables, there were some cables that went between the command module and the lunar module during coast to the moon where we powered some heaters in the lunar module for the two or three day trip to the moon. So that you wouldnt use any of the power out of the batteries that you needed for the lunar module on the lunar surface. And those are the only cables im aware of. And those cables, like bill said, they kept the heaters going on our inertia measurement unit, the platform that told you where you were in space and that kind of thing when you powered it up. But those cables came to be very important on apollo 13. Because we were able to use them , the Battery Power to recharge the reentry batteries on the command module so they could reenter safely. Yes or against the wall. Why were they so far off the lunar surface when they landed . The landing gear, the original intent was it would automatically land and as jack said, literally what was going to happen was when these probes were about 4 feet tall, when they were to hit, it would actually shut the engine off and drop. We learned very quickly in simulations that that is not what neil had in mind, and i dont think as a pilot i would have done that either. So none of the apollo landings were anywhere near as strong. But if the engine had quit at 10 feet or 12 or 13 feet, it was designed to survive that fall. It was going to survive by stroking the landing. Yes, it had a honeycomb that would compress. So you didnt want the latter to stop it from compressing. There was no spring or anything in the landing gear, it was honeycomb Aluminum Structure inside a tube so it was just a oneshot deal. And it would crush and the strut would compress but he landed so light that it didnt compress very far and thats why the latter was as high as it was. Who was responsible for picking and packaging and mounting the us flag and the top is straight because of the support arm but what about the bottom . s back my recollection of that, that was designed by our Tech Services division here at the space center. Headed by john kiker and they came up with the concept of unfurling the flag with the support at the top and just let it hang, it was 1 6 gravity and it was all compressed until, into a small package before it was deployed. And we have one in the control center just like that and in fact one of the flags in the control center, i forget what mission they took it from the control center and fluid to the mont, the moon but its just like that. Did Neil Armstrong typically land with 10 to 20 seconds one of them he didnt land, he ejected out of it. I think thats right. The only ones that you would leave for some other reason or an engine problem or a leak in the sent the ascent, so with the landings we always had four or 5 remaining. The question was its called Mission Control but who is actually in control, was that the people on the ground or the people in the spacecraft . The control covers a lot of ground. The crew could manually control a lot of things within the vehicle but the flight ops team what they are constantly doing is keeping track of the flight plan and any changes to the activities we are going to do, and any changes to any procedures that we are going to do and working any anomalies that occur, with the spacecraft. Its a joint effort between the crew and the ground. You are constantly going back and forth. In those days we didnt have a lot of the command capability they have today, so you would put together procedures, read them up and the crew would work through the switches, where today a lot of that stuff is done by command. From the ground. Let me ask you, are you meaning who is an ultimate command of making a decision . Is that what youre talking about also . The ground computer complex did almost all of the trajectory calculations and generated a set of numbers that were sent up to the spacecraft which they entered into their computers. So without the ground they would not have had enough computational power to do the whole mission. Once you got into powered descent there was nothing that ground could do if the crew wanted to keep going. So if thats what youre talking about, but if the ground called an abort, most chances they would abort because they would assume that ground saw something they could not see. I think another part of that is that the, in Mission Control it is the flight director that makes in a critical situation, makes those decisions based on his team on the ground and longerterm he actually gets management that sits behind him and makes those decisions. But the decision whether or not to recommend the abort comes from the flight director and goes directly to there was three consoles that had the abort switch. Flight director, flight mechanics officer. That was almost always associated with a launch vehicle. None of those abort buttons worked when she got out we have time for one last question. Can somebody enter that in five words . My guess would have been the 1202 alarm. The first one because it was just unexpected, it was not a normal thing, we had done it in simulations but nobody really expected that it would happen and then because of the simulations, they had set up a situation, we had gone and done a bunch of research to figure out what alarms would be a real problem and whatnot. And jack garman had a list, that he worked out with mit who did all the programming on this thing. During simulations he had punched out and aborted when he got that alarm but we had had all those discussions and reviews and he decided it was okay. That points out the real unsung heroes, theres just so many and some all of this country, but the simulations guys were just amazing. They had to not only learn the systems and how they worked and look at our procedures but then try to find areas and in the very last film, the 1201 actually came up and that was the emphasis for looking into that and that is just a perfect example of the teamwork that it took to pull this mission off. Another way to describe the simulation people, they were very devious. [ laughter ] on that note ladies and gentlemen thank you very much for being here. Thank you panelists. [ applause ] all week we are featuring American History tv programs as a preview of whats available all weekend on cspan three. Lectures in history, american artifacts, real america, the civil war, oral history, the presidency, and special event coverage about our nations history. Enjoy American History tv now and every weekend on cspan three. Here is a look at our prime time schedule on the cspan networks starting at 80 stern on cspan, remarks from afl cio resident on the Labor Movement and involvement in the 2020 elections, on cspan 2 it is authors that have written recent bestsellers and on c span3 its American History tv with programs on marijuana regulation in the us. Watch American History tv for starting at it covers Justice Ruth Bader ginsburg on her book my own words, david trigger his book is the heart beat of wounded knee. Sharon robinson talks about her book child of the dream. Rick atkinson author of the british are coming and Thomas Malone founding director of the mit center for collective intelligence discusses his book super mines. The National Book festival Live Saturday at 10 am eastern on book tv. On cspan 2. Labor day weekend on American History tv saturday at 8 pm eastern on lectures in history, a discussion about Abraham Lincoln and native americans. Sunday at 4 pm on real america the 1950 army film invasion of southern france. And monday, labor day, at 8 pm eastern, the commemoration of the 400th anniversary of virginias first gen. Assembly held at jamestown. Explore our nations past on American History tv. Every weekend on cspan3. University of california irvine english professor book thomas delivered a talk titled the politics of popular portrayals of Andrew Johnsons impeachment. Prof. Thomas discussed three examples, thomas dixon juniors 1905 novel the klansman, the 1942 hollywood film tennessee johnson, and the impeachment story as told by sen. John f. Kennedy in his 1957 blitzer prizewinning book profiles in courage. This event was part of a symposium on reconstruction, hosted by the us capital historical society. Book thomas is a professor in the English Department at the university of california at irvine, i think you just took a meritless status which means he now has more time to write and more time to talk and more time to educate all of us and i am honored that he has come here again. He was here a couple of years ago and i am honored that he is back today. [ applause ]